Vertical tubular bagging machines are known, with which top-side and bottom-side welded, filled tubular bags are manufactured. A foil tube is for this purpose initially longitudinally welded. Then the foil tube is filled, is welded transversely to its transport direction, and a finished tubular bag is separated from the foil tube.
Many different drives and gearings are known to operate the welding jaws, which carry out the cross-welding of the foil tube in order to produce the top and bottom seams of the tubular bags.
A device for welding of a foil tube is known from the DE 196 27 892 A1, which device, is suited for this cross-welding.
The foil tube is in this known device welded by means of two welding jaws, which are movable against one another and clamp the foil tube between one another, each one jaw holder serves thereby to hold one welding jaw and each one jaw carrier to carry one jaw holder and thus a welding jaw. A linear drive with a part movable linearly along an active line is provided as the drive. A gearing is connected to the movable part, whereby the gearing is also connected to the jaw carriers in order to produce an opposing movement of the jaw carriers and thus of the welding jaws in order to be able to move the welding jaws toward one another and away from one another. One joint each is thereby provided on the jaw carriers in order to pivotally connect rods of the gearing to the jaw carriers.
The known device has the disadvantage that it has a rod, which serves as a lever to enlarge the welding pressure. This rod reaches downwardly to the linear drive and results together with same in a relatively high construction for this device, which in practice can result in a space problem on a vertical tubular bagging machine.